Relative path to CSS and JS files hosted with Godaddy does not work

Question

I am setting up a site on the Godaddy provider and I have a problem causing the CSS and JS settings to be applied on the site, because it appears all without marking.

I ran a test to check if the address passed on link href is correct and successful.

I ran a test using a if inside the archive index.php, file this giving fault.

$filename = '../assets/_css/0_css_dashboard.css';
if (file_exists($filename)) {
    echo "O arquivo $filename existe";
} else {
    echo "O arquivo $filename não existe";
}

and the response of if was that the file exists...
Any idea what might be happening or if I need to apply the link in another way?